1. Field of the Invention
The present invention relates to an apparatus and method for processing is parallel digital signals, indicating an ON or OFF state of a plurality of circuit breakers, inputted from the plurality of circuit breakers.
2. Description of the Related Art
In general, a circuit breaker is a power switching device for providing an electric power, which is to be inputted to an industrial load device, or breaking an electric power supply according to the state or size of an electric current of a circuit connected by a control signal. In general, a power distributing board installed at an electrical power incoming section of a substation or a large-scale electric power consumer includes a main circuit breaker for switching a main circuit of led power and a plurality of sub-circuit breakers for switching a plurality of distributing circuits, and performs a function of managing a state of the circuit breakers or monitoring a state of a switching operation of the circuit breakers.
In the power distributing board, a monitoring device such as a digital relay receives digital input signals, indicating an ON/OFF or trip state, transferred from the plurality of circuit breakers, so the received digital input signals need to be processed.
FIG. 1 is a schematic block diagram of an apparatus for processing a plurality of digital input signals according to the related art.
As shown in FIG. 1, an apparatus 4 for processing a plurality of digital input signals outputted from a plurality of circuit breakers according to the related art includes a plurality of digital input signal input terminals 1 that receive signals, in parallel, outputted from the circuit breakers, photo couplers 2 that insulates noise so as not to be transferred, and transfers only the digital input signals, and a central processing unit (abbreviated as CPU hereinafter) 3 that receives the plurality of digital data, in parallel, transferred from the plurality of photo couplers 2, and process them.
One of the relates arts is configured such that the photo couplers is not provided and the digital input signals are directly inputted to the CPU 3 without passing through the photo couplers 2.
The plurality of digital input signals may include, besides signals indicating an ON/OFF or trip status of the circuit breaker, digital input signals transferred from industrial devices such as motors, pumps, valves, and the like. The digital input signals provide information required for a user to monitor and manage the corresponding circuit breaker or the industrial devices.
However, the related art apparatus and method for processing digital input signals have the following problems.
That is, because the plurality of digital input signals are inputted and processed in parallel, the same number of photo couplers as the number of the digital input signals, the same number of input and output ports of the CPU as the number of the digital input signals are required, for which, thus, a Printed Circuit Board (abbreviated as PCB hereinafter) having a larger area is required to cause a problem in that the size of the monitoring and managing apparatus increases.
In addition, when the input ports of the CPU are limitedly used or when the monitoring and managing apparatus is configured based on digital input signals with a limited PCB, only information particularly required by the user or only some of a plurality of received digital input signals are limitedly processed by the CPU according to the intention of a developer who develops a corresponding apparatus is/are processed, causing a problem in that the function of the monitoring and managing apparatus is limited.